Processes for breaking petroleum emulsions



PROCESSES FOR BREAKING rsmomum EMULSIONS Melvin De Groote, St. Louis, and Arthur F. Wirtel, Kirkwood, Mo., assignors to 'lretolitc Company, Webster Groves, Mo., a corporation of Missouri 1 Application September 18, 1936, Serial No. 101,434

6 Claims. (cl. 196-4) No Drawing.

This invention relates to the treatment of emulsions of mineral oil and water, such as petroleum emulsions, for the purposeof separating the oil from the water.

amylamine to produce materials such as l-monoamyl amino propane-2,3-diol or l-di-amyl amino propane-2,3-diol (see U. S. Letters Patent No.

2,042,621, to Olin, dated June 2, 1936).

of the primary amine, so as to give a di-hydroxy Petroleum emulsions are of the water-in-oil If glycerol mono-chlorhydrin is replaced by a 5 type, and comprise fine droplets of naturally-0c mono-chlorhydrin derived from a glycol, for incurring waters or brines, dispersed in a more or stance, ethylene glycol mono-chlorhydrln, proless permanent state throughout the oil which "pylene glycol mono-chlorhydrin, butylene glycol constitutes the continuous phase of the emulmono-chlor y amylene glycol mono-chlflrr 10 sion. They are obtained from producing wells hydrin, hexylene glycol mono-chlorhydrin, etc., 10

and from the bottom of oil storage tanks, and one obtains products which are somewhat similar are commonly referred to as cut oil, roily to the v amino p p derivatives P v y oil, emulsified oil and bottom settlings. mentio edrbllt are n act, y m y y y The object of our invention is to provide a amines. For the purposes of illust ethylnovel and inexpensive process for separating e yc C o yd m y kill-Own as emulsions of the character referred to into. their glycol thylene) chlor yd l be employed- .component parts of oil and water or brine. The most suitable compounds are derived from Briefly described, our process consists in subamylamines, and more particularly, from monojecting a petroleum emulsion of the water-in-oil amylamine, although it is to be noted that any type to the action of a treating agent, or desuitable aliphatic primary or secondary amine 20 mulsifying agent of the kind hereinafter de-. may be employ T reaction may be 111115- scribed, thereby causing the emulsion to break trated as follows: down and separate into its component parts of oil and water or brine, when the emulsion is per- (13mm 1 HEN (05111:) CHIHMCSHU) :mitted to remain in a quiescent state after -treat-- email 25 ment, or is subjected to other equivalent separa- In the event that di-amylamine is employed.

Y procedures. the resultant product would be:

The treating agent or demulsifying agent contemplated' by our process consists of or com- 30 prisesan alkylated naphthalene sulfonic acid in CHi-OH 3: fqrm 9 bydroxyalkyl'alkylamme salt The products so obtained may be either e.k1nd in which at least one of the alkyl hydmmlkybmonmalkylammes or hydroxy groups substituted in the naphthalene nucleus alkyl di alkylamiues contains not less than three carbon atoms and Not only may reations the m above re 35 '3 lmfre l i g Such prod ferred to' be employed to produce products or c S ale fa l pm 1 materials of the kind used as the demulsifying briiifg iiie53235221"iill filfilitfisiiiiui agent in our m but one may also produce i products or materials by reactions involving an 40 among other substances, substituted polycyclic alkylene oxide and a suitable primary or 40 aromatic sulfonic acids, or the r salts. The type ondary amine: Ethylene oxide may react with which finds most frequent; application is ob monmamylanfinebaslindicatedby the following tamed by introducing one, two or more alkyl reaction: '7 groups into'a naphthalene residue and then producing the sulfonic acid, or-the equivalent pro- 45 cedure of alkylating the sulfonicacids. Due to mwn) E the corrosiveness of the sulfonic acid, it isthe CH: Bron usual practice to employ the reagent in the 7 form of a salt, such as ammonium salt, potas S a ly, when ethy e Oxide is reacted with 5:1) salt Sodium m t '-:{gr di-amylamine, the corresponding compound pre- We havefound that if the alkylated aromatic viously described, that is:

sulfonic acids of the kind previously described are. neutralized by means of a hydroxyalkyl- (can):

. alkylamine'of the kind previously referred to and smog of the. kind that will be hereinafter described in is formed; However, by either the reaction ingreater detail, one obtains a treating agent or volving chlorhydrin or by the reaction involving demulsifying agent of unusual effectiveness. the alkylene oxide; two molecules of the oxide or It is known that glycerol mono-chlorhydrin the chlorhydrin can be united with one molecule may be reacted with mono-amylamine or di- 0 one or two, with the proviso that m plus in di-ethyl mono-alkylamine, as indicated by the following reactions:

The present process employs alkylated naphthalene sulfonlc acids which have been neutralized by hydroxyalkyl-alkylamines of the kind previously described, and which may be indicated by the following formula:

in which T is an alkylene radical of the conventional formula type CnH2n, B is analkyl radical having two or more carbon atoms, m represents the numeral one or two, m represents the numera1 zero or one, and m" represents the numeral plus m" equals three.

As previously pointed out, glycols or alkylene glycols are characterized by the formula CnH2n(OH) 2 and include ethylene glycol, butylene glycol, propylene glycol, amylene glycol, hexylene glycol, etc. In some instances, the glycols may exist in isomeric forms, and it is intended that all isomeric forms be included, because one form is just as suitable as another. Propylene glycol is just as suitable as trimethylene glycol. Other glycols suitable for use include heptamethylene glycol, momomethylene glycol, decamethylene glycol, undecamethylene glycol, tridecamethylene glycol, tetradecamethylene glycol, and octadecamethylene glycol.

In the illustration referred to previously, reference has been made to mono-amylamine and di-amylamine, since this alkylamine is available in the open market at the lowest price. Any other suitable alkylamine, and preferably, alkylamines having at least four carbon atoms and not more than eightcarbon atoms, are equally suitable. Itis known, of course, that the various primary and secondary amines may occur in more than one isomeric form. For instance, the expression -alkylamine" is not intended to differentiate between isomeric forms, as, for example, an amylamine where the alkyl group may have a straight chain form or a branched form. Primary and secondary butylamine, amylamine, hexylamine, heptylamine and octylamine appear to be the most satisfactory amines for reaction with the alkylene oxides or glycol chlorhydrins.

Piperidine (hexahydro-pyridine) is not a true aliphatic amine from the strictest structural standpoint, but is comonly recognized as having the properties of an aliphatic amine. Hence, it is intended-that .piperid-ine be included in the broad classification of alkylamines. Smith, A Textbook of Organic Chemistry, 1932, second edition, revised, p. 646, states as follows: Whereas, pyridine is a weak tertiary base of aromatic character, piperidine is a strong secondary base,

the entire behavior of which classifies it with the aliphatic amines."

There does not appear to be any suitable explanation of the unusual superiority of the demulsifying agent employed in the present process, and similarly, there does not seem to be any basis by which one could anticipate or foresee this unusual ei'fectiveness. Apparently, this marked improvement is not directly related to oil or water solubility, insofar that similar neutralization with other amines may yield compounds. which have a greater solubility in oily materials or in water, and yet are not nearly as suitable and not nearly as eflective in their demulsifying action.

Apparently, there is some unlooked-for cooperation or chemical or physico-chemical relationship between hydroxyalkyl-alkylamine residue and the sulfo-aromatic residue. The neutralization of other conventional acidic demulsifying reagents with hydroxyalkyl-alkylamines does not seem to produce any marked improvement over the corresponding sodium .or ammonium salts, and in many cases, yields an inferior product, thus indicating that apparently the increased value does not reside in an additive effect, due to the hydroxyalkyl-alkylamine residue. If one neutralizes other sulfonic acids, which are known to be efiective demulsifying agents, such as petroleum sulfonic acids of the mahogany acid type, with a hydroxyalkyl-alkylamine, one does not obtain a more efiective demulsifying agent, and indeed, one is more likely to obtain a demulsifying agent which is less eifective. Based on the results of actual tests obtained in a variety of emulsified crudes occurring in a number of the major oil fields of the United States, the conclusion one must inevitably reach is, that the result obtained by uniting the two residues, i. e., the hydroxyalkylalkylamine residue and the described sulfo-aromatic residue in a singlemolecule,results in an unlocked for, unique quality, which could not be foreseen by the present knowledge of the art, and which produces a demulsifying agent that is particularly efiective for a large number of emulsified crude oils Alkylated naphthalene sulfonic acids are produced commercially, and the salts are used for a variety of purposes. They are generally produced from naphthalene, because there does not appear to be any advantage in the use of a naphthalene derivative, such as chlor-naphthalene, alpha and beta naphthol, etc. In other words, one could introduce the sulfonic acid residue and the alkyl residues into a substituted naphthalene, such as chlor-naphthalene, etc., just as readily perhaps as in the case of naphthalene. Such simple derivatives, of course, are the chemical equivalent of naphthalene in the manufacture of such sulfonic acids as are employed in the manufacture of the present reagent. It is understood that the word naphthalene is hereinafter employed to include these derivatives.

The general process of manufacturing the demulsifying agent contemplated by our process, consists in converting the naphthalene into either the alpha or beta naphthalene sulfonic acid, or a mixture of the two, or in some instances, into a di-, or even a tri-sulfonic acid, or a mixture of the various types. In most instances there is no advantage in introducing more than one sulfonic acid residue. In many instances it is unnecessary to use particular care to prepare either only the alpha sulfonic acid, or either only the beta sulfonic acid, because a mixture in which either one or the other predominates, or a mixture in which the alpha and beta sulfonic acids are as satisfactory as one sulfonic acid completely freed from the other type. I

The alcohol employed, such as various propyl alcohol, butyl alcohols, amyl alcohols, hexyl alcohols, decyl alcohols, etc. is converted into the acid sulfate, such as propyl hydrogen sulfate. The naphthalene sulfonic acid and the alkyl hydrogen sulfate are combined in proportions so that one, two, three, or even four alkyl groups are introduced into the aromatic residue. This condensation reaction is generally carried out in the presence of an excess of sulfuric acid. In some instances, the various reactions, such as sulfonation, sulfation, condensation, etc. are car ried out simultaneously. Generally speaking, the di-alkylated and tri-alkylated' material appear to yield the most desirable type of reagent. The presence of some monmalkylated material, or some tetra-alkylated material is not objectionable, and may even be desirable.

It is obvious, of course, that the alkylated groups introduced might be derived from olefines, such as butylene, propylene, amylene, etc., insofar that such olefines react directly with sulfuric acid, to produce the alkyl hydrogen sulfates. of course, in addition to introducing such alkyl residues of the kind described into the aromatic nucleus, one could also introduce an alkyl residue from some other alcohol, as, for example, an alkylated group derived from ethyl or methyl alcohol, or one might introduce a group derived rfirom an aryl, aralkyl, hydro-aromatic, or cycle cc alcohol, but regardless otwhether or not one introduces such other residues, it is necessary that at least one alkyl residue of the kind described, i. e., having at least three carbon atoms and not more than ten carbon atoms, be introduced into the naphthalene ring. Such compounds having some other residue present, such as methyl residue, might be considered as being derived from methyl naphthalene, instead of naphthalene, and thus, would fall within the class of chemical equivalents previously noted. It is immaterial as to the particular alcohol employed, or the particular isomeric form of the alcohol employed, although generally speaking, it is most desirable to use the one lowest in cost. It is immaterial whether one uses normal propyl alcohol or isopropyl alcohol. whether one uses a normal butyl or isobutyl al cohol. It is immaterial whether the alcohol be a primary alcohol, or a secondary alcohol, or a tertiary alcohol, or the like.

It is obvious that a large number of isomers can be produced in the manufacture of the material employed as the demulsifying agent in the present process. For instance, although the sulfonic group may be introduced into either the alpha or beta position, it is manifest that the alkyl group or groups can be introduced into the other.

various positions in regard to the position of the sulfonic acid'residue.

Apparently, as far as we are aware, one isomeric form is as eifective as Reference to the compounds is not intended to indicate any particular isomer, un-

Gil

less the text clearly indicates some specific position.

Insofar thatthe most readily available alcohols, from the standpoint of cost, are isopropyl alcohol, normal butyl alcohol, isobutyl alcohol, and aniyl-alcohol; it is our preference to produce our demulsifying agent from these alcohols, and in some instances, it is desirable to introduce dif- It is immaterial ing process which removes the excess of sulfuric acid or. other sulfonation, sulfation, or condensation reagent employed. Theacidic mass thus obtained is neutralized with a hydroxylalkyl-alkylamine in the same manner than sodium or potassium or ammonium hydroxides might usually be employed. The finalproduct, if it represents a pasty or semi-solid or a solid mass, is rendered suitable for industrial use by the addition of a solvent, such as water, an alcohol, a coal car product, a petroleum hydrocarbon solvent or in any similar manner.

The demulsifying agent that we prefer to use in practising our process is obtained by areastion in which three molecules of isopropyl alcohol are united with one molecule of naphthalene by the customary sulfation, sulfonation and condensation reactions. The resulting mixture consists largely of di-propyl naphthalene sulionic acids and tri-propyl naphthalene sulfonie acids, with possibly small amounts of mono-propyl sulfonic acids and tetrapropyl sulfonic acids present. Generally speaking, it is easier to conduct the reaction so that the bulk of the sulionic acid represents the beta type, although the alpha type may be produced, if desired. The product is neutralized with hydroxyethyl-amylamine derived by reaction between ethylene glycol chlorhydrin and mono-amylamine, and may consist of a mixture of mono-hydroxyethyl-amylamine, and di-hydroxy di-ethyl-amylamine. The product so obtained is diluted with one or more solvents, so as to reduce its viscosity to that of ordinary Castor oil, or slightly greater. The solvents which we preferably employ are a mixture of two or more of the following: Water, denatured alcohol, kerosene, or tar acid oil.

Among the reagents which are particularly effective are the'hydroxyalkyl-alkylamine salts of the following alkylated naphthalene sulionic acids, i. e., mono-isopropyl naphthalene sulfonic acids, di-isopropyl naphthalene sulfonic acids, tri-isopropyl naphthalene sulfonic acids, mononormal butyl naphthalene sulfonic acids, dl-normal butyl naphthalene sulfonic acids, monoisobutyl naphthalene sulfonlc acids, di-isobutyl naphthalene sulfonic acids, mono-amyl naphthalene sulfcnic acids, di-amyl naphthalene sulfonic acids, tri-amyl naphthalene sulfonic acids, mono-hexyl naphthalene sulfonic acids, di-hexyl naphthalene sulfonic acids, tri-hexyl naphthalene sulfonic acids, mono-octyl naphthalene sulfonic acids, di-octyl naphthalene sulfonic acids, mono-decyl naphthalene sulfonic acids, di-decyl naphthalene sulfonic acids, mono-isopropyl dinormal butyl naphthalene sulfonic acids, monoisopropyl mono-heron naphthalene sulfonic acids, etc.

It may be desirable to indicate that there is sometimes some variation in nomenclature in regard to the salts derived from strong acids and various amines. For instance, the combination of aniline, and hydrochloric acid, is often referred to as aniline hydrochloride. When aniline hydrochloride is treated with caustic soda, aniline is regenerated and sodium chloride is formed. For this reason, and perhaps for other reasons, structural conditions are best expressed by referring to the compound as ahydrochlorlde, in

order to indicate that one does not obtain the ,chloride of a quaternary ammonium compound. Similarly, the reaction of a hydroxyalkyl-alkylamine with a sulfonic acid may be considered as producing the hydroxyalkyl-alkylamine salt, although for reasons pointed out, such salt might be looked upon as a hydroxyalkyl-alkylamine hydrogen 'sulfonate,as well as being considered as a hydroxyalkyl-alkylamine sulfonate. Insofar-that it is perfectly clear as to the chemical composition ofthe compound, it is immaterial which nomenclature is employed.

In such instances where there is present more than one sulfonic acid residue, as in the formation of a di-sulfonic acid, or a tri-sulfonic acid, or even a tetra-sulfonic acid, if desired, all the sulfonic acid hydrogenmay be. neutralized with hydroxyalkyl-alkylamine, and the other sulfonic hydrogen'atom or atoms may be neutralized with some other suitable base, such as sodium hydroxide, potassium hydroxide, ammonium hydroxide, etc. o

Hydroxyalkyl-alkylamine salts, such as the hydrochloride, may react by double decomposition with alkali sulfonates in a suitable medium to produce the hydroxyallwl-alkylamine sulfonate.

Conventional demulsifying agents employed in the treatment of oil field emulsions are used as such, or after dilution with any suitable solvent, such as water; petroleum hydrocarbons, such as gasoline, kerosene, stove oil; a coal tar product, such as benzene, toluene, xylene, tar acid oil,

. cresol, anthracene oil, etc. Alcohols, particularly aliphatic alcohols, such as methyl alcohol, ethyl alcohol, denatured alcohol, propyl alcohols, butyl alcohols, hexyl alcohols, octyl alcohols, etc., may be employed as diluents. Miscellaneous solvents, such as pine oil, carbon tretrachloride, sulfur dioxide extract obtained in the refining of petroleum, etc., may be employed as diluents. Similarly, the material or materials employed as the demulsifying agent of our process may be admixed with one or more of the solvents customarily used in connection with conventional demulsifying agents. Moreover, said material or materials may be used alone or in admixture with other suitable well known classes of demulsifying agents, such as demulsifying agents of the modified fatty acid type, the petroleum sulfonate type, the alkylated sulfo-aromatic type, in which the sulfonic hydrogen is neutralized by the use of some base other than hydroxyalkylelkylamine.

It is well known that conventional demulsifying agents may be used in a water-soluble form, or in an oil-soluble form, or in a form exhibiting both oil and water solubility. Sometimes they may be used in a form which exhibits relatively limited water solubility and relatively limited oil solubility. However, since such reagents are sometimes used in a ratio of 1 to 10,000 or 1 to 20,000, or even 1 to 30,000, such an apparent insolubility in oil and water is not significant, because said reagents undoubtedly have solubility within the conventration employed. This same fact is true in regard to the material or materials employed as the demulsifying agent of our process.

We desire to point out that the superiority of the reagent or demulsifying agent contemplated in our process is based upon its ability to treat certain emulsions more advantageously and at a somewhat lower cost than is possible with other separation of the aqueous available demulsifiers, or conventional mixtures thereof. It is believed that the particular demulsifying agent or treating agent herein described will find comparatively limited application, so far as the majority of oil field emulsions are concerned; but we have found that such a demulsifying agent has commercial value, as it will economically break or resolve oil field emulsions in a number of cases which cannot be treated as easily or at so low a cost with the demulsifying agents heretofore available. Having thus described our invention, what we claim as new and desire to secure by Letters Patent is: I

1.A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion'to the action of a demulsifying agent comprising a hydroxy-alkyl-alkylamine ing agent comprising a, compound of the formula in which T is an alkylene radical of the conventional formula type CnHZn, B is an alkyl radical having two or more carbon atoms, m represents the numeral one or two, m represents the numeral zero or one, 121," represents the numeral one or two, with the proviso that m plus m plus m equals three; D(SO3)m"' is an alkylated naphthalene sulfonic acid residue-in which at least one alkyl group substituted in the naphthalene nucleus contains at least three carbon atoms, and m' represents the numeral one, two or three.

3. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a hydroxyallQrl-alkylamine salt of a. butylated naphthalene sulfonic acid.

4. A process for breaking petroleum emulsions of the water-in-oil type, which consists in sub- .jecting the emulsion to the action of a demulsifying agent comprising a hydroxyalkyl-alkylamine salt of an amylated naphthalene sulfonic acid.

5. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent comprising a hydroxyalkyl-alkylamine salt of apropylated naphthalenesulfonic acid.

6. A process for breaking petroleum emulsions of the water-in-oil type, which consists in subjecting the emulsion to the action of a demulsifying agent obtained or produced by converting naphthalene into the monosulfonic acid; converting propyi alcohol into the acid sulfate; combining said materials in molecular proportions in presence of sulfuric acid as a condensing agent,- followed by the conventional washing process and waste acid and neutralization of the sulfonic acid by means ofhydroxy-ethyl-amylamine, followed by addition of a suitable solvent.

MELVIN DE GROOTE. 

